diff --git a/tk.spec b/tk.spec
index 95db4bd..8237b8f 100644
--- a/tk.spec
+++ b/tk.spec
@@ -1,5 +1,4 @@
 %define majorver 8.4
-%define epoch 1
 
 Summary: Tk graphical toolkit for the Tcl scripting language
 Name: tk
@@ -10,7 +9,7 @@ License: BSD
 Group: Development/Languages
 URL: http://tcl.sourceforge.net
 Source0: http://download.sourceforge.net/tcl/%{name}%{version}-src.tar.gz
-BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root
+BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 Requires: tcl = %{epoch}:%{version}
 Requires(post): /sbin/ldconfig
 Requires(postun): /sbin/ldconfig